U.S. Pat. No. 4,497,196 describes a stamping and forming machine having aligned opposed ram assemblies which move towards and away from each other along rectilinear paths. The ram assemblies have stamping and forming tooling on their opposed faces which performs stamping and forming operations on strip material which is fed along a strip feed path that extends between the ram assemblies. The ram assemblies are reciprocated by levers which oscillate along arcuate paths and which are coupled to the ram assemblies. The couplings must be such that they are capable of accommodating the arcuate movement of the levers and transmitting forces from the levers to the ram assemblies as they reciprocate along their straight line paths. The above identified U.S. Patent describes a machine in which universal joints are used in the couplings and good service has been obtained with universal joints although they tend to wear out with time and with prolonged usage because of the friction generated or developed during operation of the machine. Application Ser. No. 915,79 filed Jul. 16, 1992 (15343) describes an improved coupling which has cylindrical bearing surfaces with the axes of the cylindrical surfaces extending normally of the path of reciprocation of the ram assembly and normally of the plane of oscillation of the actuator lever. Couplings of the type shown in that application are an improvement over universal joint type couplings for the reason that the friction is greatly reduced and longer life in the coupling is obtained.
The present invention is directed oo the achievement of an improved force transmitting coupling which applies force transmitted from an arcuately moving actuator to the axis of a ram which reciprocates along a rectilinear path. The invention is further directed to the achievement of a coupling which is essentially frictionless so that the necessity for lubricating the coupling is avoided and to the achievement of a "fail safe" coupling.